var isGreat = true;
var examMark = 100;
var fullName = "编程";
var u = undefined;
var n = null;
var numberArr = [1, 2, 3];
numberArr.push(4);
var tuples01 = ["编程", 1];
tuples01.push(2);
tuples01.push("测试", 3);
console.log(tuples01);
var person = {
    id: 1,
    name: "yu"
};
function sum(x, y, z) {
    if (y == undefined) {
        return x;
    }
    return x + y;
}
sum(1, 10);
var sumStr = function (a, b) {
    return a + b;
};
var myCallback = function (callback) {
    console.log("定义回调函数成功");
    return callback;
};
var result = myCallback(function (a, b) { return a + b; });
console.log(result("你", "好"));
var numberOrString;
numberOrString = 100;
numberOrString = "字符";
var c = numberOrString;
c.length;
function swap(arr) {
    return [arr[1], arr[0]];
}
console.log(swap([100, "编程"]));
function returnLength(arg) {
    return arg.length;
}
returnLength("编程");
returnLength(["Python", "JavaScript", "Java"]);
returnLength({ length: 100 });
var gender;
gender = "female";
var id = 1;
